Bell's palsy

This code represents an acute, idiopathic peripheral facial nerve palsy, characterized by sudden onset of unilateral facial muscle weakness or paralysis. It is a diagnosis of exclusion, meaning other causes of facial paralysis must be ruled out. The condition typically affects the seventh cranial nerve, leading to symptoms such as drooping of the mouth, inability to close the eye, and loss of taste sensation on the anterior two-thirds of the tongue.

Use this code when documentation clearly indicates a diagnosis of Bell's palsy. This applies to patients presenting with acute, unilateral facial paralysis where no other underlying cause (e.g., stroke, tumor, infection, trauma) has been identified. Supporting documentation should include a physical examination detailing facial nerve involvement and the exclusion of other etiologies.

• Ensure documentation specifies "idiopathic" or "Bell's palsy" to differentiate from other facial nerve disorders.
• Do not use this code if the facial paralysis is secondary to another condition; instead, code the underlying cause.
• Consider sequencing this code as a primary diagnosis when it is the reason for the encounter.